This invention relates to a manufacturing process for the production of consistently patterned button preforms of pigmented urea thermoplastic molding compound suitable for being thermo-compressively cast into pigmently patterned buttons containing holes formed in the molding process. More specifically, this invention relates to the production of preforms from non-polluting commercially available material which results in a button preform which can be molded with holes, and whose shelf life can be extended by re-aquivation. Prior to the advent of this process, pigmented preforms were extremely brittle and it is belived became fractured or locally pulverized when they were compressively contacted by small protrusions in the molding cavity such as are used to form holes, causing pattern distortion. To prevent this distortion, buttons containing pigmented patterns were either patterned solely about the periphery of the finished product thereby permitting granulation of the interior without causing pattern and/or color distortion or else the buttons were cast in molds which did not contain protursions for the forming of holes. Holes were subsequently drilled into the buttons after the molded goods were deflashed; thereby adding a separate and costly operation to the manufacturing process. These techniques eliminated pattern distortion caused by forming of holes but limited production and design and/or significantly increased manufacturing costs. Additionally, prior to the advent of this process, the formulation procedure employed to produce the raw thermoplastic material entailed the use of formaldehyde and other highly toxic pollutants which limits the physical location of production facilities, increases production costs due to necessitated pollution control devices and presents a potential health and environmental hazard. Furthermore, due to dehydration the finished preforms prepared by prior methods had a shelf life of not more than two months when continuously exposed to the atmosphere.
Accordingly, it is an object of the present invention to provide a procedure for the manufacture and molding of variously patterned urea thermosetting plastic button preforms from commercially available, nonpolluting urea molding compounds, to produce a fracture resistant preform having extended shelf life and which molds without pattern distortion into buttons with holes. It is another object of this invention to use adaptations of standard, commercially available machinery and equipment to produce said preforms.